Millions of people and businesses are getting "dire" internet service despite the government ploughing £1.7billion of taxpayers' money into the problem, it is claimed.
A group of more than 100 MPs has slammed connection speeds provided by BT to 5.7 million customers - particularly in rural areas - which they say is so slow it breaks regulations.
They are now calling for the huge telecoms firm to be split up from its Openreach subsidiary to end its "natural monopoly" over the UK's broadband network.
But BT said while it took any criticism seriously, but described the report as "misleading and ill-judged", claiming the proposal to break apart the business was "wrong-headed", while a Government spokesman labelled the figures "entirely misleading".
The cross-party report carries the signatures of 121 MPs, including former Tory cabinet minister Grant Shapps , Lib Dem former Scottish Secretary Alistair Carmichael, Labour MP Helen Goodman and Ukip's Douglas Carswell.
